Syntax errors not displaying in the editor panel

Hi

For some reason my editor panel is not showing any Java syntax errors, it used to show the errors (the red squigly) when I had first installed the IDE.

However, some setting changes (inadvertently) and now the only way I can see errors are in the Run view when I build the project and see a list of all build errors.

I am on  IDEA 12.0.2 community editionn using JDK 1.6.0_43 on MAC OS X 10.8.3

Thanks

Vijay